Numerical Analysis on Performance of Frame-shear Structure with High Pile under Complex Load. Jingping Yang

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1 Advanced Materials Research Submitted: ISSN: , Vols , pp Accepted: doi: / Online: Trans Tech Publications, Switzerland Numerical Analysis on Perormance o Frame-shear Structure with igh Pile under Comple Load Jingping Yang College o humanities & social sciences eilongjiang Bayi Agricultural University, Daqing Jijing1977@163.com Keywords: Frame-shear Structure, Earthquake Action, ANSYS, Numerical Simulation. Abstract. In order to acquire mechanical perormance o igh cap supporting rame-shear structure, in view o the sea high cap supporting rame-shear theory analysis and numerical simulation o structure is less, this paper perorms numerical simulation analysis or pile caps-soil-the upper structure using the inite element sotware ANSYS. Epression equation o wave orce is given, and three-dimensional inite element model is established. By Analysis the deormation and stress o pile oundation and pile caps under dierent load combinations are obtained, and the deormation, bending moment o pile top, aial orce are checked, inally the easibility o the system is veriied, and these can provide a reliable basis and reerence or reasonable design o oshore structures. igh cap supporting rame-shear structure or its strong adaptability is widely used in oshore construction system. Introduction ainan province Sanya city is the coastal city by tourism as the supporting, visitors o reception reach tens o millions o people at home and abroad every year. As hedong district o the early development high-rise buildings have sprung upon the beach water, but high-rise building on the water are near the beach, only in the high tide can contact with water, and a ew months in the erosion o the shore wind and sand, so occupancy rate is lower. In hei District development, investors require that the building etends into the water, and avoid unavorable actors about the wind and sand. Because o the particularity o construction location, make this kind o building with conventional high-rise to be dierent, coastal underwater by years o sand and soil erosion is sot and not suitable or setting up an independent oundation, thereore water management should adopt pile oundation to support the upper structure. Considering the rise and all o the sea and avoiding the room by the sea immersion, Pile oundation pile caps need to be set a certain height above the highest water, a pile supporting high cap system is ormed. By inal decision the high cap rame-shear wall structure system scheme is adopted as high-rise buildings on the water as shown in Fig.1, the plane and the pile group layout are shown in Fig.2. Scholars at home and abroad carried out a lot o analysis about the dynamic perormance o the structure under the action o the earthquake and waves, Jia Xuemin[1]gives approimately structure dynamic water action under seismic action by using the Morison equation, the literature[2] considering the dynamic water pressure on the pier, horizontal seismic response analysis is carried out or the pier-pile-soil-luid interaction system, Zhang Xuezhi[3] considers wave orce and luid solid coupling on the whar structure to carry out the dynamic calculation, the current study or the oshore structures are more concentrated in oshore platorms, bridges and structures, and the study on the high platorm supporting rame-shear wall structure is less, the upper structure and high pile cap oundation constitute the whole structure, and work together under comple eect o earthquake and wave loads. This paper carry out numerical simulation analysis on pile caps-soil-the upper structure by the inite element sotware ANSYS, By Analysis the deormation and stress o pile oundation and pile caps under dierent load combinations are obtained, and these can provide a reliable basis and reerence or reasonable design o oshore structures. All rights reserved. No part o contents o this paper may be reproduced or transmitted in any orm or by any means without the written permission o Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-21/02/16,06:25:10)

2 CBA C110BA Advanced Materials Research Vols Frame-shear wall structure Cap 98Precast concrete pile Foundation Fig.1 Schematic structure section o pile caps Fig.2 The pile cap and pile group layout The Speciic Parameters o Engineering Group piles, pile cap and the upper part o the structure plane arrangement is shown in Fig.2. The upper rame is 12 story shear wall structure, the main load-bearing members are 3 rows o 4 columns o 12 rame columns, the height o the bottom layers is 5.1m, the other layer is 3 m, the horizontal spacing is 6m, the vertical spacing is 5.1m, in order to increase the bending rigidity o the structure and to meet the needs o unction, in 1,2and4 ais decorate 3 way the asymmetric shear wall whose thickness is 250 mm. According to speciication or design o building oundation, high pile cap thickness is 1.2m, the pile group are consisted o 35 precast concrete piles with 900mm diameter, pile length is 25m, the underwater pile with eposing length is 8m. The reerence seaport hydrology criterion, the calculation height o wave action on the pile is 6m. Load and Action The Wave Load. Wave load is dynamic load which The high pile cap is perennially orced, acting on the arbitrary height Z o the pile body (rom the submarine height Z) the horizontal wave orce consists o two components: one is the column horizontal dragging orce D is caused by the horizontal velocity o wave water points movement u, the other is the column o the horizontal inertial orce I is caused by the horizontal acceleration o wave water points movement du /dt. So the ormula and the epression o the wave orce o pile body are: = D + I. (1) 1 D = CD ρau u 2. (2) du du I = ρ V0 + CmρV0. dt dt (3) ere u and du /dt represent or the horizontal velocity and acceleration o wave water points movement on the arbitrary height Z o the column ais center position; A is the unit pile high projection area with the direction o the vertical wave; V 0 is the total drainage volume o the unit column high; ρ is the average density o the local sea; C D is drag orce coeicient with the direction o the vertical pile ais; C m is added mass coeicient o considering inluence [4]. Earthquake. As everyone knows, the structural system dynamics equations under the action o the earthquake are epressed as:

3 Frontiers o Energy, Materials and Inormation Engineering [ M ]{ } [ C]{ } + [ K ]{ } = [ M ]{ } +. (4) g When structure is subjected to seismic action, at the same time with the action o the wave load, so wave orce should be considered in establishing dynamics equation, and plus the term{ } in the right-hand side. [M], [C] and [K] represent or mass, damping and stiness matrices o the structural system, the physical meaning o the other parameters is shown in the literature [5]. The two positions are shown in Fig. 3. E w is the seismic action. The particularity o the building location makes the wave orce have a certain direction in the pile, and the earthquake may come rom any direction. This article ocuses on the earthquake orce with longitudinal ais W parallel.6e Fig.3 The wave orce and location o earthquake action Fig.4 Part o inite element model Finite Element Numerical Analysis Finite Element Modeling. There is riction and end bearing orce between pile and soil, the interaction between the two, in the process o establishing a inite element model, and we think it is in harmony between them. The range o oundation soil is 15d 10d, d is the pile length, so the oundation size is 39m 22m 17m, the range o soil is large enough to absorb the stress o diusion boundary. Using the inite element sotware ANSYS to modeling, deining element type, constant and material property, three-dimensional elasticity BEAM4 element is used to simulate the upper beam columns, can output the internal orce and deormation o the rod. Caps and loors are simulated using two-dimensional SELL63 elastic shell element, and pile and soil are simulated using 3D SOLID45 solid element. Frame o beams and columns is epressed through the lines, and shear walls and loor are ormed by plane, the way o modeling rom the top to down, ater the completion o entity model we begin to grid. The local inite element model is shown in Fig. 4. Loading. Constraints would be imposed at all point at the bottom o the oundation soil, simulation o ied edge. The wave load and earthquake waves were applied to the structural system, according to the seismic ortiication intensity o local (6 degrees) and site class (class II), we could ind the characteristic period o the oundation soil. According to The Seismic Structure Design Speciication, we selected the EL-Centro wave, Tat wave and an artiicial wave as the earthquake acceleration time history curves. Analysis and Comparison o Simulation Results Deormation. Firstly, using Block Lanzcos method to carry out the modal analysis o the structural system, system natural vibration period and requency by etending the modal can be gained, and they can provide the parameters or seismic action. By ANSYS time-history post-processing dierent time structure s displacement and internal orce under the action o earthquake and waves can be obtained, Fig.5 is the displacement igure under the action earthquake and wave. At the bottom o pile, the top o pile cap, the top o 5 story building and the rame top displacement maimum D ma o our key points are, shown in Table 2. Bending deormation can be seen in the upper structure, and rame shear

4 Advanced Materials Research Vols structure deormation is still routinely consistent, because o its high stiness o pile cap with the above quality, the deormation o the pile is more obvious. It can be seen rom Table 2, only considering a kind o load is apparently negative, under multiple load the pillars displacement etreme value D ma is 68.2 mm, still less than the limit value o / 500 standards, thereore stiness meets the speciication requirements. Aial orce on the pile top is shown in Fig.6. DCBAFig.5 Deormation o the whole structure The aial orce/kn Gravity Gravity+wave Gravity+wave+earthquake The number o piles Fig.6 The pile aial orce distribution diagram Table 2 The contrast o dierent position displacement under dierent load system Position Load A Point B Point C Point D Point Weight + wave Weight+ earthquake Weight +wave+ earthquake Conclusions The upper structure in high cap supporting rame-shear wall structure and the high pile cap oundation constitute the whole structure, both work together under the action o comple earthquake and wave orce. In view o the sea high cap supporting rame-shear theory analysis and numerical simulation o structure is less, numerical simulation analysis were carried out or pile caps-soil-the upper structure by using the inite element sotware ANSYS, the deormation and stress o pile oundation and pile caps under dierent load combinations are obtained. the deormation, bending moment o pile top and aial orce have been checked, the easibility o the system is veriied, and these can provide a reliable basis and reerence or reasonable design o oshore structures. Reerences [1] Jia Xuemin: Vibration Test and Diagnosis Vol. 13(1993), p.17. (In Chinese) [2] Zheng airong: Bridge Construction Vol.4 (1992), p.67. (In Chinese) [3] Zhang Xuezhi, uang Weiping and Li uajun: Journal o Ocean University o China Vol.35 (2005), p (In Chinese) [4] Wu Chongu, Liu Beibei: Civil and Environmental Engineering, Vol.33 (2011), p. 7. (In Chinese) [5] Wang Guangyuan: Advanced structural dynamics (Chinese Architecture Industry Press, China 2005)(In Chinese)

5 Frontiers o Energy, Materials and Inormation Engineering / Numerical Analysis on Perormance o Frame-Shear Structure with igh Pile under Comple Load /